This invention relates to jackets which are to be used primarily around storage vessels containing liquid to retain any liquid which has leaked from the vessel.
It is known at present to provide a bund around storage vessels, which contain oil for example. Such bunds conventionally comprise a brick wall which surrounds the storage vessel so as to contain any liquid which has leaked from the vessel. Such bunds, however, can be space consuming and result in the creation of a permanent structure, which may be undesirable.
According to a first aspect of the invention there is provided a jacket which is adapted to enclose at least partially a liquid storage vessel, the jacket comprising a skin arranged as a plurality of folds which are capable of opening out to permit expansion of the jacket in the event of liquid escaping from said storage vessel, characterised by securing means adapted to secure the upper part of the jacket in position with respect to the vessel and to maintain the upper part of the jacket in position in the event of liquid escaping from the vessel.
The inventive jacket may be fitted, for example, to domestic and commercial oil tanks made of steel or plastics. Alternatively it may be fitted to a water tank or hot water cylinder.
Preferably the folds in the skin are arranged, in use, to extend substantially horizontally, the plurality of folds being vertically spaced-apart from one another, and preferably such folds are retained in position by a plurality of vertically extending resilient members.
The jacket preferably comprises a rigid base tray, the lower margin of the skin being sealably attached to the upstanding walls of the tray.
The tray is preferably provided with an outlet through which any leaked liquid retained by the jacket can be drained.
The jacket preferably comprises a cover which is adapted to fit the upper end of the storage vessel, and preferably the cover overlaps with the upper margin of the skin and is external thereto. Such a cover can provide protection against ingress of rainwater for an outside storage vessel.
The securing means may be positioned beneath the cover or/and the upper margin of the skin may be attached to the cover by the securing means.
The invention also comprises a hot water cylinder fitted with a jacket in accordance with the first aspect of the invention.
A hot water cylinder and jacket assembly may be provided with a float valve adapted to sense the level of any leaked water collecting in the space between the cylinder and the jacket, and operative to turn off a water supply to the cylinder.